Edgar Holmes swam at the 1904 Olympics but he is best known as a journalist, editor, coin dealer and collector, and an author on numismatics. His interest in coins was piqued in the 1870s and 1880s as a child, when he saw the design of several new coins. In 1880 he was severely injured when a shotgun blast accidentally hit him in the leg, leaving him with difficulty walking and requiring use of a cane for the rest of his life. To overcome this disability he took up swimming for exercise. Adams joined up with the Bath Beach Swimming Club and later swam for the Human Fish Club and the New York Athletic Club. He won the Metropolitan AAU Championship for plunging from 1902-05.
After the 1904 Olympics, Adams began writing a column on hobbies, especially coin and stamp collecting, for New York newspapers. He also began publishing articles in The Numismatist. He later became the editor and publisher of this magazine. He also worked in the newspaper trade early in his life as a compositor. Adams became prominent in the American Numismatic Association (ANA), serving on the Board of Governors. He declined election as a vice-president, which would have led to his becoming president. He also served on the Membership Committee of the New York Numismatic Club in 1910, and was a member of the Pacific Coast Numismatic Society, and the Chicago Numismatic Society. In addition to his journal articles, Adams later wrote several books on coin collecting. In 1969 the ANA named Edgar Adams to its Hall of Fame.